The series was a combination of episodes derived from the Railway Series, magazines stories (written by the series' current head writer, Andrew Brenner) and a couple of original stories by Allcroft and Mitton. One of the primary reasons for diverging from the original books was that many of the stories not yet used featured large numbers of new characters, which would be expensive to produce. Another reason was that the producers wanted more stories about Thomas, the nominal main character. The Rev. W. Awdry noticed the more loose adaptations and disliked the new stories citing the increased lack of realism.

Specials

Two children's television characters from Japan, Gachapin and Mukku, visit the United Kingdom. During their visit, they come to Sodor to meet Thomas, Sir Topham Hatt and the other engines. During the second half, they visit real railways and learn how steam locomotives work.

The first season broadcast when Children’s ITV was abbreviated to CITV.

From this season on, characters would angrily say "Be quiet!" instead of "Shut up!" presumably due to the production teams and script writers being accused of using an offensive phrase.

The first season to have episodes released on home video before it was broadcast on television.

In the US, this is the first season to not have a Christmas-themed season finale.

The biggest space of time between two seasons airing is between the second and third seasons. The second season first aired back in 1986 and the third season in 1992.

Gordon Goes Foreign was originally going to be an episode in this season, but it was cancelled for being too high budget. It is unknown if any of the other episodes made for this season ever replaced it.

In the Ukrainian version, Michael Angelis and George Carlin's voices can be heard in the background, as a dubbing track was not used. The first thirteen episodes have George Carlin's voice while the last thirteen episodes have Michael Angelis' voice. Angelis is also credited as narrator in the first thirteen episodes despite Carlin's narration in the background and the episodes being re-dubbed.

This is the only season dubbed by Gary Dixon and Gavin Beckwith.

For much of the season, Tidmouth Sheds appears to be much larger on the inside than in the first two seasons. While all the exterior scenes depict the shed with the usual six berths, there are nine tracks seen in most interior views.

This is the only season that has George Carlin's narration on VHS in New Zealand. However, when the third season episodes were aired on television in New Zealand, Michael Angelis' narration was used instead. This is also the case when The Complete Third Series was released on DVD in New Zealand.

Model maker John Holmes did not receive credit for working on this season until 1992.

At the very end of Michael Angelis' early narrations, the credits were shown with a still of the final shot of each 16 episodes. When shown on television and in future video and DVD releases, the credits were shown alongside a still of Thomas.

From Thomas Gets Bumped to Buzz, Buzz, each CITV broadcast featured two episodes compiled into one 10 minute block. The difference here was that only the title card for the second episode was shown after the first episode.

This season was produced in association with Fuji Television Network, Inc. as indicated by a message at the end of each episode. At the end of the first sixteen episodes, the message is in white, while at the end of the last ten episodes, it is yellow.

According to The Thomas the Tank Engine Man, it cost £1.3 million to produce all 26 episodes.

The Flying Scotsman makes an obscured appearance once in this season. He is not fully shown until 24 years later with the release of the special, The Great Race.

The last 10 episodes of this season, from Buzz, Buzz to Thomas and Percy's Christmas Adventure, were all filmed in a different period after the previous 16 episodes (evidences such as S.S. Roxstar gaining red smokestacks, Thomas' red lining in his cab and Henry's brake pipes being removed, teeth were added to Percy's laughing face from the second season (which were not present in a deleted scene from Thomas, Percy and the Post Train), as well as various set locations from he first 16 episodes, such as Knapford or Tidmouth Hault, not appearing in the later 10, and vice-versa, such as Tidmouth or Arlesburgh Harbour) and some slight changes on the details on the sets present in both periods.